1. Field of the Invention
The present application relates to an illumination device, such as it may be used for 3D LCD flat image displays (LCD=liquid crystal display) with desired autostereoscopic properties in the form of an OLED backlight.
2. Description of the Related Art
Based on luminous elements, such as OLEDs (organic light emitting diode), novel flat displays and/or flat image displays with many advantages may be realized. These advantages are the large-area deposition of, for example, the organic substances on various substrates and the self-luminous properties of the displays, thus allowing very thin displays.
Here, solutions for non-adaptive, passive backlight applications of OLEDs for LC displays (liquid crystal displays) are applied in the displays.
U.S. Pat. No. 5,965,907 teaches a backlight based on an OLED for liquid crystal applications. The backlight includes a first OLED multi-layer structure capable of emitting light in a red frequency spectrum, a second OLED multi-layer structure adjacent to the first OLED multi-layer structure and capable of emitting light in a green frequency spectrum, and a third OLED multi-layer structure adjacent to the second OLED multi-layer structure and capable of emitting light in a blue frequency spectrum. A liquid crystal display is put on the top face of the light-emitting device. The device may be used as color image display in portable electronic appliances.
US 2005/007517 A1 teaches the use of an OLED backlight integrated in a liquid crystal display. The liquid crystal display has three substrates, wherein one of the three substrates is associated with the OLED and the liquid crystal display. The common substrate has two surfaces, one of the two surfaces having a transparent electrode, a polarization filter and an adaptation layer for the liquid crystal element. This one of the two surfaces is opposite to the top substrate of the liquid crystal display having the same layers. A thin liquid crystal film is located between the two substrates. The second surface of the common substrate has an active organic layer including an anode and a cathode and is opposite to the bottom substrate of the OLED backlight. The two faces of the common substrate are hermetically sealed with respect to the two other substrates of the liquid crystal display and the OLED. When the organic light-emitting diode is activated as backlight, the light it generates is launched into the liquid crystal display.
US 2004/0164292 A1 shows a device that comprises a first electrode including a reflective material and a second electrode located above the first electrode and having a translucent material. An organic layer comprising a light-emitting material is located between the first electrode and the second electrode. A light-modulating element is located above the second electrode. The first electrode may be implemented as the only effective reflective layer in the device, or the first and the second electrode and the organic layer are located above the light-modulating element, and the second electrode is reflective, while the first electrode is non-reflective.
Color displays may be produced by the use of color filters. There may be used OLEDs emitting a broad light spectrum, such as white light, or emitting light of a single color or light of various colors.
US 2001/0030320 A1 shows an OLED device capable of using light transmitted from the side. The OLED device includes an OLED comprising a substrate surface and having side faces for the emission of photons. Furthermore, the OLED device comprises at least one light-bundling means adjacent to the OLED, which bundles the emitted light so that the deflected light is parallel to the light emitted from the surface of the substrate.
However, none of the known devices is suited to adjust the direction of the light emitted from a display. Particularly, none of the known OLED arrangements can provide an indication of an electronically controllable functionality of an OLED backlight application and its realization to be able to actively generate desired autostereoscopic effects for a 3D display.